Márcia de Mello Luvielmo

Xanthan gum: Production, recovery, properties and application

As bacterias pertencentes ao genero Xanthomonas podem produzir goma xantana, um polissacarideo de enorme interesse para as industrias de alimentos, farmaceuticas e de petroleo. A goma apresenta capacidade de formar solucoes viscosas e geis hidrossoluveis que lhe fornece propriedades reologicas unicas. Atualmente toda a goma xantana consumida no Brasil, provem de importacoes, porem o Brasil tem um grande potencial para a fabricacao deste polimero em escala industrial, ja que temos materia-prima basica para sua producao: acucar, extrato de levedura e alcool do setor sucro-alcooleiro. O objetivo dessa revisao e atualizar os conhecimentos sobre a producao, recuperacao, propriedades e aplicacao da goma xantana. The bacteria belonging to the gender Xanthomonas can produce xanthan gum, a polysaccharide of enormous interest fo r food, pharmaceutical and petroleum industries. The gum presents capacity to form viscous solutions and gels hydrosoluble that supplies its unique reological properties. Actually, all xanthan gum consumed in Brazil, becomes from imports, however Brazil ha s a great potential for production of this polymeric in industrial scale, since we have basic raw material for its production: sugar, yeast extract and alcohol of sugar-alcohol section. The objective of this review is to update the knowledge about production, recovery, properties and application of the xanthan gum.

Adjuncts used for beer production: Features and applications

Among the raw materials used for beer production, barley malt is the most widely used to provide the necessary carbohydrates to yeasts during fermentation, in which alcohol and carbon dioxide are produced. Must supplementation with adjuncts is recommended to correct properties that were not reached but this should not affect beer quality. Thus, the aim of this review is to present the main raw materials used to replace barley malt. Cereals and starchy materials can be used as starchy adjuncts, such as corn gritz , rice, wheat. Another group of adjuncts, known as sugary adjuncts, also has wide applications. They do not need to suffer enzymatic hydrolysis, because their sugars are readily fermentable. The adjuncts, in general, are used to decrease production costs since they allow the use of reduced energy during processing. Key words: beer, adjuncts, fermentation.